Releasable ski boot heel binding

ABSTRACT

In a releasable ski boot heel binding comprising a base to be attached to a ski, a casing having a boot heel engaging member at its front end, and a supporting member mounted to the base and pivotably connecting the casing, a cam member is swingably connected to the front portion of the supporting member. The cam member is urged and press-fitted to a transverse pin, which is connected to the front portion of the casing, by a depressing spring. The cam member has a dented portion in which normally the transverse pin engages and a protruded portion against which the transverse pin acts to force back the cam member.

United States Patent 1 Hashioka [54] RELEASABLE SKI BOOT HEEL BINDING [75] Inventor: Noliyasu Hashioka, Kita-ku, Tokyo,

Japan [73] Assignee: Hope Kabushiki Kaisha, Tokyo,

Japan [22] Filed: May 13, 1971 [21] Appl. No.: 143,145

[30] Foreign Application Priority Data May 23, 1970 Japan ..45 44231 [52] US. Cl. ..280/l1.35 T [51] Int. Cl ..A63c 9/00 [58] Field of Search ..280/11.35 T

[5 6] References Cited UNITED STATES PATENTS 3,317,217 5/1967 Poiger ..280/l1.35 T

[ 1 May 22, 1973 Primary Examiner1(enneth H. Betts Assistant Examiner-Robert R. Song Attarney-Fleit, Gipple & Jacobson [57] ABSTRACT In a releasable ski boot heel binding comprising a base to be attached to a ski, a casing having a boot heel engaging member at its front end, and a supporting member mounted to the base and pivotably connecting the casing, a cam member is swingably connected to the front portion of the supporting member. The cam member is urged and press-fitted to a transverse pin, which is connected to the front portion of the easing, by a depressing spring. The cam member has a dented portion in which normally the transverse pin engages and a protruded portion against which the transverse pin acts to force back the cam member.

7 Claims, 3 Drawing Figures PATENTED MY 22 I975 FIG.

INVENTOR. l ya u Hashio'ka RELEASABLE SKI BOOT HEEL BING This invention relates to a releasable ski boot heel binding to be attached to the top surface of a ski in cooperation with a ski boot toe fixture, and more particularly to a ski boot heel binding wherein a depressing spring urges a cam member swingably connected to a supporting member to a horizontal transverse pin secured to a boot heel engaging casing.

In a known releasable ski boot heel binding adapting toggle link levers comprising a fore link and a swinging link pivoted with each other at one end thereof, a depressing spring normally presses down the fore link, which other end is connected to a boot heel engaging casing, to engage the boot heel in the casing. But, when an abnormal severe upward thrust is applied to the boot heel, the fore link rotates against the compression force of the depressing spring and throws up the casing to release the boot heel therefrom as soon as the fore link passes beyond the dynamic production of the spring.

Such known releasable ski boot heel binding has advantages that the relatively small compression fore of the depressing spring is converted to a larger engaging force by means of the toggle link levers and that the casing is instantaneously displaced to the boot heel releasing position when the fore link passes beyond the dynamic production of the depressing spring.

However, some disadvantages have been experienced in such ski boot heel bindings due to the toggle link levers themselves. Firstly, degrees of rotation of the fore link toward the boot heel releasing position against the compression force of the depressing spring increase in proportion to upward thrust applied to the boot heel. Therefore, when an upward thrust not so strong to rotate the fore link beyond the dynamic production of the depressing spring is increasingly applied to and eliminated from the boot heel, the casing engaging the boot heel will reciprocate due to vertical play of the fore link. Such dangerous relatively wide vertical play of the fore link cannot be eliminated from the boot heel binding adapting the toggle link levers.

Such conventional ski boot heel binding, in which the boot heel engaging casing is increasingly displaced in proportion to the upward thrust applied to the boot heel, is said to lack in elasticity or, to say other words, to absorb small amount of upward thrust energy.

The wide vertical play of the casing occured in the known binding is undesirable, but, from the viewpoint of safety of a user, a minimum vertical play is rather desirable to absorb a relatively small non-dangerous upward thrust.

Therefore, as the improvement of the known ski boot heel bindings, it is desired to provide a ski boot heel binding which has larger elasticity or absorbs large amount of upward thrust energy until it is displaced to the boot heel relasing position with a minimum vertical play of the casing.

Another disadvantage experienced in the ski boot heel bindings adapting the toggle link levers is that the boot heel engaging force greatly depends upon the arrangement of the fore link and the swinging link.

Namely, in the boot heel engaging position, the forelink is at its front end connected to the boot heel engaging casing at a point more advanced than an extension line of the swinging link to form an acute angle therebetween. The engagingforce produced by the depressing spring acting on the links is inverse proportion to the degrees of the acute angle. This means that, when the swinging link and the fore link are arranged substantially on a straight line, the engaging force due to the depressing spring is great. On the other hand, when the acute angle becomes large, the engaging force is inversely proportionally weak.

Therefor, in manufacturing of such ski boot heel bindings, the arrangement of the links to obtain the predetermined engaging force is one of the most difficult and delicate problems. For this reason, some percents of the manufactured bindings may not have substantially same engaging force.

Another disadvantage experienced in the ski boot heel bindings adapting the toggle link levers is that many kinds of conditions of elasticity or absorbing conditions of upward thrust energy cannot be obtained to correspond to skiers skill.

An object of the present invention is therefor to provide a ski boot heel binding which, compared with the conventional ski boot heel bindings, has larger elasticity or absorbs a larger amount of upward thrust energy until it is displaced to the boot heel releasing position with a minimum vertical play.

Another object of the present invention is to provide a ski boot heel binding which can be manufactured easily with a uniform prescribed engaging force.

Another object of the present invention is to provide ski boot heel bindings which can satisfy many conditions of elasticity or many absorbing conditions of up ward thrust energy to correspond to skiers skill.

A releasable ski boot heel binding according to the present invention comprises a base to be attached to a ski, a casing having a boot heel engaging member at its front end and a transverse pin connected at its front portion, a supporting member mounted to said base and pivotably connecting said casing, a cam member swingably connected to the front portion of said supporting member, said cam member having a dented portion in which normally said transverse pin engages and a protruded portion against which said transverse pin acts to force back said cam member, and a depressing spring urging and press-fitting said cam member to said transverse pin.

The cam member can be designed as desired. For example, when a larger amount of upward thrust is to be absorbed to give much elasticity to the binding for use of skilled skiers with a minimum vertical play of the casing, the protruded portion of the cam member is steeply protruded. On the other hand, when a smaller amount of upward thrust energy is to be absorbed to give a less elasticity to the binding for use of beginners with an allowable vertical play of the casing, the protruded portion of the cam member is gradually smoothly protruded.

The present invention is so constructed that, in either case of the cam profiles mentioned above, the absorbing amounts of the upward thrust energy are greater than those obtained in the boot heel bindings adapting the toggle link levers. This will become apparent when the both of the present and conventional bindings are compared as follows. After setting the both bindings so as to disengage the boot heel at same value of upward thrust, upward thrust enough to start compressing each of the depressing springs of the bindings is increasingly applied to each casing. In the conventional boot heel binding, the fore link rotates about a pivot connecting one end thereof to the swinging link in proportion to the increasing of the upward thrust, with the result that the casing is proportionally displaced toward the boot heel releasing position. On the other hand, ever when such increased upward thrust strong enough to displace the casing of the conventional binding to a certain rotated position is applied to the present binding, the casing of the present binding is not displaced to such rotated position as the conventional one since the horizontal pin secured to the casing of the present binding cannot proportionally come over the protruded portion of the cam member by the increasing upward thrust to the casing. Thus, the present binding absorbs more upward thrust energy with less vertical play than the conventional binding. Such binding is said to have much elasticity than the conventional binding.

Preferably, in order to displace the casing to the boot heel releasing position at users will, a L-shaped unlocking member is provided to project outside of the casing. The unlocking member is pivoted to the supporting member and is operatively connected at its inner end to the cam member through a connecting lever, so that, when the unlocking lever is pushed down, for example, by a ski pole, the cam member is pulled back against the depressing spring and forces up the horizontal pin beyond the protruded portion of the cam member, thereby displacing the casing to the boot heel releasing position.

Furthermore, in order to adjust the horizontal force of the binding against the boot heel, another compression spring is provided within the supporting member along the longitudinal direction of the ski. The fore end of the spring is received by a spring-receiving member fixed to the supporting member and the other rear end thereof is received by another spring-receiving member which arms are movably fitted into slots in the supporting member. An adjusting screw passes through the rear spring-receiving member and, thereby, moves back and forth the binding along the base by rotation thereof so as to adjust the horizontal force of the binding and to precisely fit the binding to many sizes of ski boots.

All of the afore-mentioned as well as additional features of the present invention will become more clearly apparent from the following detailed description thereof, which is to be read with reference to the accompanying drawings, in which,

FIG. 1 is a partially sectioned side view showing a releasable ski boot heel binding in the boot heel engaging position according to a first embodiment of the present invention,

FIG. 2 is a partially sectioned side view of the same binding in the boot heel releasing position, and

FIG. 3 is a sectioned side view showing only main parts of a releasable ski boot heel according to a second embodiment of the present invention.

Referring to FIGS. 1 and 2 showing a first embodiment of the present invention, reference numeral 16 designates a base to be attached to the top surface of a ski. The base is provided at both sides thereof with guide flanges 12 the front portion of which are provided with fixing holes 11. The rear end of the base 16 is folded upright to define a vertical wall 13. Side frames 20 opposed with each other are provided at the lower end thereof with horizontal grooves which are slidably engaged with the guide flanges 12 of the base 10. The side frames are set to the opposite relation by three pins 22, 23 and 24 passing therebetween. Each of the side frames 20 is provided at the lower portion thereof with restricted slot 21 through which sidewardly extending projections or arms 17 at the front end of a spring-receiving member 16 is movably engaged. The spring-receiving member 16 is threaded by an adjusting screw 15 which also threads through a hole 14 in the vertical wall 13 of the base 10. A spring 19 is compressed in parallel to the base between the spring-receiving member 16 and another springreceiving member 18 secured to the pin 23 between the side frames 20.

A casing 30 having a boot heel engaging member 31 and a boot heei receiving member 32 covers the side frames 24) and is pivoted thereto by the pin 24. At the upper front portion of the side frames 20, opposite rocking plates 25 are pivoted by the pin 22. A cam member 34 is interposed between the opposite rocking plates 25 and is integrally connected thereto. Alternatively, the cam member 34 may be integrally formed with the rocking plates 25. On a pin 26 passing through the rocking plates 25 and the cam member 34, an front end of a connecting lever 27 is pivoted, the other rear end thereof being pivoted to a front end of a L-shaped unlocking lever 29. The unlocking lever 29 is rockably connected to the side frames 20 by the pin 24.

As is clearly shown in FIGS. 1 and 2, the profile of the cam member 34 comprises a major circular section of small radius and a minor circular section of large radius. The front conjunction of the large and small circular sections forms a dented portion and the small circular section continuing to the dented portion forms a smoothly protruded portion.

A horizontal transverse pin 33 is provided at the front lower portion of the casing 30 so that, in the boot heel engaging position or locking position shown in FIG. 1, the pin may locate at the dented portion of the cam member 34. A depressing spring 35 is interposed between a spring-receiving member 36 pivoted to the rockable plates 25 and another spring-receiving member 33 threaded by another adjusting screw 37. The adjusting screw 37 also passes through the upper back portion of the casing 30 to adjust the compression force of the depressingspring 35. The depressing spring thus urges the cam member 34 toward the pin 33.

In normal skiing, the horizontal pin 33 is engaged into the dented portion of the cam member 34 by action of the depressing spring 35. However, when an abnormal thrust caused by such as falling of a user is applied to the boot heel engaging member 31 through his boot heel, the horizontal pin 33 receives the thrust through the casing 30 to rotate about the pin 24. Then, the horizontal pin 33 is disengaged from the dented portion and, rotating about the pin 24, it begins to rise the protruded portion of the cam member 34 and forces back the cam member about the pin 22. As soon as the horizontal pin 33 passes over the foremost protruded portion of the cam member 34, the horizontal pin 33 is thrown up as shown in FIG. 2 by the action of the depressing spring 35.

This releasable ski boot heel binding in the locking position shown in FIG. 1 is also displaced at will to the unlocking position by operating the unlocking lever 29. When the unlocking lever 29 is pushed down, the connecting link 27 pulls back the cam member 34 against the depressing spring 35. As soon as the horizontal pin 33 passes over the foremost protruded portion of the cam member 34, the casing 30 is thrown up in the same way as mentioned above.

To engage the boot heel to this binding, one may only to set his boot heel bottom to the boot heel receiving member 32 in the unlocking position and step down this member. In this time, the horizontal pin 33 pressfitting to the upper front portion of the cam member 34 forces back the cam member 34 against the depressing spring 35 as it goes down. As soon as the horizontal pin 33 passes over the foremost protruded portion of the cam member it is instantaneously fitted into the dented portion thereof and firmly engaged therein by the restored compression force of the depressing spring In a second embodiment shown in FIG. 3, a cam member 40 having a different cam profile from that of the first embodiment is swingably pivoted to a pin 22 on which opposite rocking plates 25 are also swingably pivoted as in the first embodiment. The cam member 40 is also connected to the rocking plates 25 by a pin 26 on which a connecting lever 27 are pivoted. 'll-lerefore, the cam member 40 as well as the rocking plates 25 are integrally swingable about the pin 22 secured to the side frames 20. A spring-receiving member 36 by which the front end of a depressing spring 35 is received is pivoted to the rocking plates 25 at the back of the cam member 40.

The cam member 40 has, at its front portions to be cooperated with a horizontal pin 33, a dented portion 41, a steeply protruded portion 42 and a upper slant The horizontal pin 33 is secured to side frames at its both ends of reduced diameter and, in the locking position, the dented portion 41 of the cam member 40 is urged against the pin 33. Thus, in normal skiing, the

- horizontal pin 33 cannot move to rise on the steeply protruded portion 42 of the cam member 40 due to the pressure of the depressing spring 35. But, when an ab normal upward thrust is applied to the boot heel engaging member 31, the horizontal pin 31 will come to rise the protruded portion 42 of the cam member 40. As

soon as the horizontal pin 33 reaches to the top of the protruded portion 42 of the cam member 40 by forcing back the cam member 40 and the opposite plates against the compression force of the depressing spring 35, the depressing spring contributes to swing the cam member 40 forwardly to displace the horizontal pin 33 to the upper slant portion 43 of the cam member 40, so that the casing is displaced about a pin 24 to the unlocking position. Other remaining respects are substantially same as those of the first embodiment.

In the second embodiment, though the cam member 40 is connected to the opposite rocking plates by the pins 22 and 26, they may be formed integrally with each other. Furthermore, the horizontal pin 33 secured to the casing 30 to frictionally contact to the cam member 40 may be a roller supported on the pin 33 to reduce the friction therebetween. In view of the frictional portion 43. As shown in FIG. 3, the dented portion 41 contact of the horizontal pin 33 to the cam member 40, preferably the cam member 40 is made of synthetic resin such as sold in the market under a trade mark Derlin.

The ski boot heel binding according to the second embodiment of the present invention has a less vertical play of the casing than that of the first embodiment and will be acceptable for skilled skiers. V

Many modifications and alternations may be made within the spirit of the present invention.

What is claimed is:

l. A releasable ski boot heel binding comprising a base which is adapted to be attached to a ski, a casing,

a boot heel engaging member at the front end of said thereto, a cam member swingably connected at its 4 upper portion about a transverse horizontal axis to the front portion of said supporting member, said cam member having a dented portion in which said transverse pin is normally engaged and a protruding portion against which said transverse pin acts to force said cam member rearward during release, and a depressing spring slanted downward in the forward direction exerting its force at a point rearwardly of said dented portion and urging said cam member against said transverse pin in the boot engaging position.

2. A releasable ski boot heel binding as claimed in claim 1, wherein said protruding portion of said cam member is steeply projected forwardly from said dented portion thereof and terminates in a relatively smooth slanted portion.

3. A releasable ski boot heel binding as claimed in claim 1, wherein opposed rocking plates are pivoted to said supporting member and said cam member is integrally connected to said opposed rocking plates and is urged forward by said depressing spring, and further comprising a spring-receiving member at the front end of said depressing spring and pivoted to said rocking plate at the back of said cam member.

4. A-releasable ski boot heel binding as claimed in claim 3 wherein said cam member is made of hard synthetic resin.

5. A releasable ski boot heel binding as claimed in claim 1, and further comprising a roller in combination with said transverse pin, said roller being press-fitted to said cam member and being rotatable along the surface of said cam member.

6. A releasable ski boot heel binding as claimed in claim 1, wherein said supporting member comprises a pair of opposed side frames slidably engaging said base, and further comprising a compressed spring' positioned parallel to said base and urging said side frames forward.

'7. A releasable ski boot heel binding as claimed in claim 1 further comprising an unlocking lever having a connecting link, the front end of said unlocking lever being operatively connected to said cam member through said connecting link, the other end of said unlocking lever projecting outside of said casing. 

1. A releasable ski boot heel binding comprising a base which is adapted to be attached to a ski, a casing, a boot heel engaging member at the front end of said casing, a transverse pin connected at the front portion of said casing, a supporting member mounted to said base and having said casing pivotably connected thereto, a cam member swingably connected at its upper portion about a transverse horizontal axis to the front portion of said supporting member, said cam member having a dented portion in which said transverse pin is normally engaged and a protruding portion against which said transverse pin acts to force said cam member rearward during release, and a depressing spring slanted downward in the forward direction exerting its force at a point rearwardly of said dented portion and urging said cam member against said transverse pin in the boot engaging position.
 2. A releasable ski boot heel binding as claimed in claim 1, wherein said protruding portion of said cam member is steeply projected forwardly from said dented portion thereof and terminates in a relatively smooth slanted portion.
 3. A releasable ski boot heel binding as claimed in claim 1, wherein opposed rocking plates are pivoted to said supporting member and said caM member is integrally connected to said opposed rocking plates and is urged forward by said depressing spring, and further comprising a spring-receiving member at the front end of said depressing spring and pivoted to said rocking plate at the back of said cam member.
 4. A releasable ski boot heel binding as claimed in claim 3 wherein said cam member is made of hard synthetic resin.
 5. A releasable ski boot heel binding as claimed in claim 1, and further comprising a roller in combination with said transverse pin, said roller being press-fitted to said cam member and being rotatable along the surface of said cam member.
 6. A releasable ski boot heel binding as claimed in claim 1, wherein said supporting member comprises a pair of opposed side frames slidably engaging said base, and further comprising a compressed spring positioned parallel to said base and urging said side frames forward.
 7. A releasable ski boot heel binding as claimed in claim 1 further comprising an unlocking lever having a connecting link, the front end of said unlocking lever being operatively connected to said cam member through said connecting link, the other end of said unlocking lever projecting outside of said casing. 